Concept:The chemical formula determines the fixed ratio of elements inside a compound. We can use this ratio to find the amount of the entire compound based on the mass of a single element within it.
Formula:$$ \text{Moles of compound} = \frac{\text{Given mass of element}}{\text{Mass of element in 1 mole of compound}} $$
Solution:- One mole of \( \text{CO}_2 \) contains 1 atom of Carbon and 2 atoms of Oxygen.
- The mass of Oxygen in 1 complete mole of \( \text{CO}_2 \) is \( 2 \times 16 \text{ g} = 32 \text{ g} \).
- We are provided with exactly 8.00g of Oxygen.
- To find the corresponding moles of \( \text{CO}_2 \): \( n = 8.00 \text{ g} / 32 \text{ g/mol} \).
- \( n = 1/4 = 0.25 \text{ moles} \).
Why other options are incorrect:- 1.00: This would be the answer if the question asked for 32g of oxygen.
- 0.75 & 1.50: Arise from incorrect assumptions about the molar mass of oxygen atoms vs. diatomic oxygen gas.
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